Piston-rod packing



(No Model.) J. H. MOG'OWAN.

PISTON ROD PAGKING.

N0. 347,817. Patented Aug. 24, 1886.

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I enior Zm'in asses: Z0. 6'. Jz'rd 17255072. 0* M BMW 3 N4 PETERS,Finale-Lithographer, Wilhillslwfl. D4 (Iv NITED STATES PATENT OFFI JOHNH. MOGOIVAN, OF CINCINNATI, OHIO.

PISTON-ROD PACKING.

EPECIPICATION forming part of Letters Patent No. 347,817, dated August24,1886.

Application filed May 12, 1886. Serial No. 201,906. (No model.)

To all whom it may concern.-

Be it known that I, J OHN H. McGowan, a citizen of the United States,residing at Cincinnati, Ohio, have invented new and useful Improvementsin Piston Rod Packing, of which the following is a specification.

My invention relates to the means of packing externally the piston-rodsor plungers in structures in which two or more cylinders or chambers (asin steam-pumps, 850.) are arranged separately or tandem in relation to acommon rod or plunger, its object being to simplify the structure byutilizing one gland or stuffing-box for packing the two contiguousentrances of the rod into adjacent cylinders; also, to prevent theexternal leakage occurring in such structures where independent packingsare used, and to prevent access of dust and dirt to the packing.

To this end my invention consist-s in the provision upon' each cylinderor chamber of a sleeve extending toward the other, and embracing thepiston-rod or plunger,with asuitable interval between the contiguousends of said sleeves, forming a recess for the packing around the rod orplunger, one of said sleeves being of smaller diameter than the other,and in the combination therewith of an outer casing or collar,constituting the stuffing box proper, fitted snugly over the end ofthelarger sleeve, and extending thence as a casing of uniform diameterover and beyond the end of the smaller sleeve, thus inclosing an annularpacking-space of two diameters, of which the piston-rod or plunger formsthe axial core of a portion, and the smaller sleeve the axial core ofthe remainder. The said casing may be adjustable longitudinally, or itsend wall surrounding the smaller sleeve may be formed as anindependently-adjustable gland, so thatin setting up either or both thepacking will be compressed in its inclosing-space surrounding thepiston-rod.

' Mechanism embodying myinvention is illustrated in the accompanyingdrawings, in which Figure 1 is a side elevation of two cylindersarranged tandem in relation to a common piston-rod or plunger, and of myinvention as applied thereto; Fig. 2, avertical longitudinal section ofthe packing devices; Fig. 3, a similar section showing thepacking-collar engaging by screw-threads in lieu of the retainingbolts;Figs. 4 and 5, axial sections of constructive modifications.

Referring now to the drawings, A and Bdesignate two cylinders orchambers arranged in the same axial line, in which a common piston-rodor plunger, P, opcratesan arrangement common in duplex steam-pumps,steamengines, and other structures. Heretofore in such structures it hasbeen common to apply separate stuffing boxes and packing at theplunger-entrances of each cylinder, with an interval in which the rod orplunger was entirely exposed. The disadvantages of this constructionare, among others, that the two separate packings produce excessivefriction and wear of the parts, and that the leakage is external andobjectionable, and that the entire exposure of the plunger between thestuffing-boxes facilitates access of dirt, and consequent destructivewear of the rod and packing.

In my improvement I dispense entirely with the ordinarystuffing-boxes,and apply the fol lowing construction: The cylinder A,for example, is provided with a sleeve, a, extending beyond the head andsurrounding the piston, closely fitting the front opening of astuffing-box or collar, 0, and the cylinder B is provided with a sleeve,1), extending in the opposite direction from its head to within a shortdistance of the end of sleeve a, inclosing the same rod or plunger, P,and fitting closely the rear opening of the collar 0. The stufling-boxor collar 0 is cup-shaped, with perforated bottom to slip over thesleeve 1), and may have a marginal flange, c, for the engagement of adjusting-bolts d, as shown in Fig. 2, or may engage the sleeve a byscrewthreads, as in Fig. 3.

To describe more fully the details of the construction shown in Figs. 2and 3, the annular thickness of the sleeve a is equal, say,to thediameters of two (radially-imposed) layers of v the packing, the annularthickness of the sleeve 6' equal to that of one such layer, thelongitudinal interval between the ends of sleeves a 1) equal to that oftwo or more such layers, and the longitudinal depth of the box 0sufficieut to lap somewhat over the sleeve a and extend sufficientlybeyond the end of sleeve 1) to allow several of the packing-coils towind around the sleeve 1) within the box 0. The construction here shownand described is preferablein larger structures where round or or fiatrope packing isused. It will be seen that upon setting up the box orcollar 0 by its adj listing-bolts d the entire mass of packing will becompressed,with the effect of forcing it into the space between the endsof the sleeves a I), around the plunger 1?, thus packing both theopenings in the sleeves at once. It will also be seen that no externalleakage can take place from the box or collar 0, as the packing is notsubjected to wear at the outer portions, and therefore remains al waysin perfect condition. \Vhatever leakage oecurs,therefore,if any,isforced through from one cylinder to the other. It will be obvious thatin this case the sleeve 1) must be of sufficient length to allow the boxor collar G to be slipped back far enough to uncover the space betweenthe two sleeves and permit the insertion of new packing.

In Figs. 4 and 51 have shown aslight modi fication of structure, inwhich the box 0 is constructed as a mere collar fully open at both ends,and an independent adjustable gland, D, is used to close the openingaround the sleeve b. Both the collar 0 and the gland D may be securedadjustably by screw-threads, as in Fig. 5, or by retaining-bolts d d andflanges c c c", as in Fig. 4. By the employment of the independent nutor gland D the renewal of the packing is facilitated, as a small portionmay be added from time to time, to replace that lost by wear, byremoving the small gland D,without disturbing the main packing-box orcollar 0. The proportions and relative arrangement of the parts andpacking here shown are illus-' trative merely, and may be varied withoutdeparting from the spirit of my invention. The kind of packing to beused is not material. Thus, the ordinary metallic split or seetionalrings may be used adjacent to the rod in the space between the ends ofthe sleeves, with fibrous packing surrounding it and filling theremainder of the packing-space, and the joints made tight by setting upthe collar. 0 or gland D, either of which latter may be adjustedindependently of the other. This I have indicated in Fig. 5.

In Figs. 2 and 3 I have shown the end of the larger sleeve, a,countersunkand the corresponding end of the sleeve 1) beveled orconical. This construction I deem preferable where cotton yarn or othersoft packing of any kind is used; but where metallic rings are used Ideem it preferable to have the ends of the sleeves dressed to planesurfaces, as indicated in Figs. 4 and 5.

I claim as m invention and desire to secure by Letters Patent of theUnitedStates- 1. In combination with two independent cylinders orchambers arranged tandem upon the same piston-rod or plunger, anextension from each cylinder or chamber surrounding the piston-rod orplunger as a sleeve, leaving a space between the ends of the sleeves,and a single packing-box or collar'surrounding the ends of the sleevesand covering the intervening space around the rod or plunger,substantially as set forth.

2. In combination with two independent cylinders or chambers arrangedtandem upon the same piston-rod or plunger, two sleeveextensions ofdifl'erentdiameters embracing the piston-rod or plunger between thecylinders or chambers, and a packing-box or collar inclosing the ends ofthe sleeves and forming an annular packing-space surrounding the pistonbetween the sleeves and extending inward'beyond the end of the smallersleeve, substantially as set forth.

3. The combination of the cylinders A B, provided with the separatesleeve-extensions a b, with the piston-rod or plunger P and thepacking-box or collar 0, substantially as set forth.

4. In combination with the cylinders A B, piston P, andsleeve-extensions a b, of different diameters, the adjustable collar 0,provided with the gland D, substantially as set forth.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

JOHN H. MCGOW AN.

\Vitnesses:

L. M. HOSEA, O. D. KERR.

